JP2003519894A - Microwave system with two magnetrons and method of controlling this system - Google Patents

Abstract

Abstract: A heating system or microwave treatment system for a substance or object having an applicator or oven (5) provided by two separate magnetrons (11, 12) is disclosed. A magnetron is mounted on the coupling branch (3,4) of the magic T-coupler or directional coupler forming a ring. The other coupling branches (1,2) irradiate the substance (10). Impedance adapters (8,9) are coupled to the branches (3,4) and / or to the magnetrons (11,12) to decouple the operation of the magnetron and to transfer the total power emitted from the magnetron to the substance or object. ). According to the described method, for example, by adjusting the impedance adapter with the aid of a dual balanced mixer, a constant and uniform maximum distribution for the substance or object, or conversely, a modulation according to the substance or object The obtained distribution can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION

Making a microwave applicator for heating a given product with a given contour is always a special case. Many solutions have been proposed, but none is sufficient and universal to solve all the problems raised by engineers. The basis of the construction of a domestic oven, the multimodal cavity, works in an optimal way for products with a volume close to 1 dm ³ . For smaller or larger volume products, the efficiency of this oven is second order. The heating time must be prohibitively long for many mid-industrial uses.

For example, consider the case of warming a roll containing meat or cheese pieces taken from a freezer kept at -18 ° C. Heating to a temperature of 35 ° C. in a household microwave oven with 800 W power requires 5 minutes of heating.

Let us assume that we know how to guide the radiant energy emitted by a generator into a conduit of the same size as an object. Wave penetration into the product is about 2 cm. This means that if we ignore the reflection of the wave from the entrance surface of the object, or by adapting the received power by placing a suitable impedance adapter in front of it, the wave will be halved every 4 cm. It means to decay and cross an object. Given the thickness of the object, one third of the incident force will exit the object through the opposite surface. Although it is possible to reflect this power back to the object, the product may burn at the inlet surface before it heats up at the opposite surface of the product, since the inlet surface is always heated more than the opposite surface.

In EP 0 136 453, to improve this situation, it is proposed that the power emitted by the magnetron be bisected and radiated to each side of the object. The distribution of the electromagnetic field in the object is symmetric and can be fine-tuned. It is possible to transmit the total power emitted from the magnetron via the adaptation, which consists of two, one on each side. The adapter neutralizes the reflections from the surface and the waves sent through the product.

However, the problem is complicated when the heating of the object requires the use of two magnetrons at a time, since the power emitted by a single magnetron is too low. As each surface is radiated by one magnetron, the transmitted waves interfere with the action of another magnetron, sometimes leading to tube destruction. Solutions have been often described for deflecting the incident waves and rotating the deflection of the waves with respect to each other. As is well known, it is not always applicable or efficient, as the transmitted waves often have multi-mode polarization due to diffraction phenomena that occur on both sides of the object.

[0006] Similarly, solutions have been advocated in which the radiation source is not continuous and emits its power alternately in a pulsed timetable. As a result, waves emanating from one of the magnetrons and arriving at the other magnetron will arrive only while the other magnetron is off. This decoupling, although effective, has shown its limitations.

The invention described below enables the waves emitted from each magnetron to be decoupled in a complete manner using magic tees or other directional couplers.

Thus, continuing with the above example with the matter fixed, a roll containing meat pieces or cheese pieces taken from a freezer kept at 18 ° C., according to the invention, is not about 5 minutes, but about 30 minutes. Can be heated in seconds.

The present invention relates to a microwave heating or processing system for materials supplied by two separate magnetrons. The magnetron is mounted on the magic tee or the coupling branch of the directional coupler, the other coupling branch forms a ring to irradiate the substance, and the impedance adapter decouples the action of the magnetron to generate the power emitted from the magnetron. To a substance or object, located in a lateral branch and / or in front of a magnetron.

The present invention describes a system with two magnetrons for separating the distributions coming from each of the two magnetrons from the electromagnetic field distributions generated by them, with the aid of dual balanced mixers. Regarding control method.

The method is conveniently automated and, according to a feedback control process, a dual balanced mixer continuously adjusts the adapter so as to optimize the aperture parameters of the magnetron.

In this way, a uniform and constant distribution is obtained for the substance or object. If necessary, the adjustment can also be controlled so that it is distributed in the field in a modulated or non-uniform manner, for example the maximum distribution of the object core and less surface.

A corresponding system for microwave heating or processing of materials is capable of canceling the applicator or oven supplied by two or more magnetrons and the waves reflected by the applicators and received by each of the magnetrons. And several impedance adapters. One or more dual balanced mixers, whose reference is supplied by the magnetron and which adjusts the impedance adapter to transmit all the power emitted by the magnetron to the material, out of all the waves it receives The share of the waves emitted from the magnetron is detected.

In yet another aspect, the invention relates to a microwave heating or processing system for materials,
This system includes applicators supplied by two or more magnetrons and some adjustments that allow partial modification of the waves emitted from each of the magnetrons, transmitted to the applicator and reflected by said applicator. And a circuit. One or more dual balanced mixers, whose reference path is supplied by the magnetron, adjusts a circuit that partially modifies the distribution of the electromagnetic field acting on the material so that it transmits the total power emitted by the magnetron, Among all the waves received, the distribution of the waves emitted by each of the other magnetrons is detected.

In the last two cases, the reference path of the dual mixer is supplied by an auxiliary generator that stabilizes its frequency to one frequency of the magnetron, the frequency of which is shifted from the frequency of the magnetron by a fixed value. Is supplied from the magnetron to the reference path of the dual balanced mixer after signal level equalization.

In such a relationship, it is possible to use four dual balanced mixers, as will be described in detail below. For further optimization, there are 6 dual balanced mixers in total. The two additional mixers are used for measurements made directly or very close to the substance or object receiving microwaves or the core of the product.

[0017]

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be better understood with reference to the accompanying figures, which are merely given by way of non-limiting example.

How to operate the device will be readily understood with the aid of FIGS. 1 and 2. A heated object or substance 10 placed in a microwave applicator or oven 5 is illuminated by symmetrical coupling branches (waveguides) 1 and 2 of a magic tee (T). The other coupling branch (waveguide) 3 and 4, orthogonal to the other two branches as shown in FIG. 2, comprises microwave radiation sources or magnetrons 11 and 12, indicated by double arrows. The branches 1 and 2 are of equal length and their arrangement is perfectly symmetrical. As a whole, the waveguides 1 and 2 form a ring-shaped or ring-conduit-shaped waveguide.

The energy emitted from the magnetron 11 originating from the branch 3 does not exit through the branch 4. It splits at the tee level, resulting in two waves of the same phase in branches 1 and 2. Each of these waves is on surface 1 of substance 10.
It is reflected at 3 and 14. They remain in phase, join at the tee and are added together in branch 3. These reflected waves are canceled at branch 4 due to symmetry. Therefore, it is sufficient to arrange two impedance adapters 6, 7 symmetrically in the branches 1, 2 in front of both sides of the object 10 so as to cancel these reflected waves. If the objects do not absorb any energy, the transmitted waves are themselves in phase. It will also come together at tee level in branch three. Therefore, it is necessary to arrange the third adapter 8 in the branch 3 in front of the magnetron 11 so that those reflected waves do not reach the magnetron 11 and do not interfere with the operation of the magnetron 11.

The magnetron 12 located in the branch 4 operates in the same way. Branch 4 emits a wave with opposite phase to branches 1 and 2, the wave having a clearly opposite phase on surface 101.
And reflected from 102. At the tee, if the symmetric adapters 6,7 in front of faces 101 and 102 eliminate these reflections, they are canceled at branch 3 and added together at branch 4 as described above. The magnetron 12 receives no energy. Also, as mentioned above, the waves originating from and transmitted by the magnetron 12 are in opposite phase. They are countered on branch 3 of the tee and come together on branch 4 of the magnetron 12 that emitted them. A fourth impedance adapter 9 placed in front of the magnetron 12 prevents waves from reaching it.

The decoupling between the two magnetrons is thus as complete as possible.
No waves emitted by magnetron 11 reach magnetron 12 and vice versa. Furthermore, the reflection of the waves emitted by each magnetron and received by each magnetron can be reduced by the individually acting impedance adapters.

Such impedance adapters 6, 7, 8, 9 are shown in FIG. They are, for example, of the plunger type with threads and enjoy two degrees of freedom in terms of insertion and height into the waveguide along f1 and longitudinal points along f2. An example of an adapter that has a rod 6 and a slot 6 ').

As shown in FIG. 4, this device has the additional advantage of achieving a uniform distribution of the electromagnetic field in the product. This FIG. 4 shows the ordinate of mV and the magnetrons 11 and 12
2A and 2B show the amplitudes E1 and E2 of the electric fields individually irradiated by. The electric field related to the total energy comes from their conjugation: E ^* = E ₁ + E ₂ . Ideally, E ^* is the horizon.

The stationary distribution of the electromagnetic field produced by the magnetron 11 is symmetrical between the two impedance adapters 6, 7. The field shows a maximum at the center of the object 10, eg curve (11) in FIG. The distribution shows maxima and minima, which are somewhat pronounced depending on the wave attenuation in the product. The distance between two consecutive maxima is equal to the halved wavelength in the material.

The stationary distribution of the electromagnetic field produced by the magnetron 12 is
Corresponding to waves of the same amplitude, but the wave distributions are in opposite phase. The stationary distribution is shifted by a quarter of a wavelength such that its maximum is located where the minimum of the stationary distribution of the field emitted by the magnetron 11 is located.

The energy E ^* dissipated in the product is proportional to the sum of the field squares of the individual distributions. It has been found that heating is much more uniform if both distributions are considered, rather than each. If the relative amplitudes of the two distributions are not as desired, the local division of energy is departed from the scope of the invention by fine-tuning the lateral impedance adapters 6,7 located in branches 1 and 2. Can be adjusted without. Then, indeed, since the device has an impedance adapter 8, 9 in front of each magnetron, the waves reflected by the magnetron will no longer be negated. Since the waves to be corrected in front of each magnetron are truly emanating from each magnetron, it will be clear how to correct the adjustments in said magnetron.

The invention described uses a magic tee (T) to decouple the action of two magnetrons that are emitted sequentially, and the invention also operates one magnetron with respect to another magnetron. Applies to magnetron. The present invention enhances the decoupling that can provide this solution. Similarly, the invention is combined with the conventional means described above. This means is to rotate the plane of deflection of the transmitted and reflected waves, or of the emitted waves.

It would be within the scope of the invention to place the magnetron in branches 1 and 2 of the magic tee while feeding the applicator through branches 3 and 4. The operating method may be shown in the same way.

Magic tees other than the tees shown in FIG. 2 may be used provided that they work differently in the same shape.

Similarly, a 3db directional coupler, referred to as a 90 degree tee, can be used. This combiner consists of two conduits with a regular opening on the regular small side. This tee has a different plane of symmetry than the magic tee. That is, the waves coming through the coupling branches 1 and 2 are in quadrature with each other at 3 and 4 regardless of the radiation source. Given that different lengths of branches 1 and 2 (by λ _g / 4) are chosen, this difference is equivalent to the situation illustrated by conventional magic tees.

Similarly, without departing from the scope of the invention, it is possible to use a directional coupler with a coupling coefficient different by 3 db, for example 10 db, with two generators having the same power output or different power outputs. Wave circulation occurs as described above. The stationary distribution is obviously modified in amplitude and can benefit from it, for example to heat a surface of the object for a desired time.

If the price of an industrial magnetron is rapidly higher than the power output in a general way, the use of two lower power magnetrons is a very economical solution compared to the use of a single magnetron. become.

It should be noted that the present invention does not have anything similar to some high frequency or microwave radiation source assemblies or devices called combiners. These devices have two or three branches. These serve to divide into two or three amplifiers or synchronous radiation sources, ie synchronous radiation sources fed by exactly the same preamplifier. With these devices, wave combination occurs only because the radiation sources are synchronous.

The present invention is an applicator divided into two parts or two that operate in the same way.
It does not use and is not characteristic of a magic tee with a single generator feeding two applicators. This device is designed to optimize the absorption in the two applicators without adjustment, as shown for example in FR 2 316 761, whose individual reflected waves vary equally strongly during the process. I use magic tea.

A first spatial arrangement of the system according to the invention is shown, for example, in FIG. The reference numbers there are borrowed from FIGS. 1 to 3 for the same or to perform the same function as the members shown in FIGS. Microwave applicator 5
Alternatively, the oven contains the product 10 to be treated. An applicator is depicted that allows this product 10 to be inserted into and withdrawn from the applicator by a door. .

The magic tee (T) is a branch 3 and 4 which starts from the magnetrons 11 and 12 respectively, and which leads to the applicator 5 or ends with a ring-shaped conduit consisting of the waveguides 1 and 2, that is, the coupling position of the waveguides. It is in. The waveguide is, for example, a standard 86 × 43 mm
It is a square type. The ring may have an annular or elliptical shape, or a straight portion may be bent.

In this case, the positions of the adapters 6, 7, 8, 9 can be finally adjusted for the optimum distribution according to the microwave energy of the present invention received by the product starting from the magnetrons 11, 12. .

The device described in the present invention may also be automated. Its use can be justified by this fact alone. In particular, if the dielectric properties of the product to be processed change, or if the product has a varying shape, the adjustment of the adapter of the device of FIGS. 1 and 2, as will be apparent with reference to FIG. It can be fully automated.

For example, during heating or cooking, the product being treated often swells and vice versa. The dielectric properties then generally change, in which case it is advantageous to be able to modify the adjustment accordingly as a function of time and applied power.

To do this, sensors 13, 14 in the form of directional measuring couplers are arranged in front of each magnetron 11, 12. These sensors can measure the incident power Pi and the reflected power Pr by the respective magnetrons 11 and 12. Four dual balanced mixers are used to detect the microwave signal. It should be noted that the device also has an antenna or sensor 15 that is slipped in the immediate vicinity of the product to be processed or in the core of the product. This point will be described in detail below. That is, after showing other geometries of the system of the present invention, corresponding reference numerals indicate identical or functionally identical parts.

In fact, FIG. 7 shows another device of this system. Here, the oven 5 is a parallelepiped instead of a cone, and the waveguide 1 is provided between the oven and the waveguide (branches 1 and 2).
6 and 17 are respectively inclined with respect to the branches 1 and 2 and are orthogonal to each other. These two complementary waveguides 16 and 17 act on the orientation of the electric field vector, thereby adjusting the relative values of the complex coefficients of reflection and transmission and, if necessary, enhancing the decoupling of the magnetron. to enable.

FIG. 8 shows yet another device. Here four magnetrons 11, 12; 11 '
, 12 'as a set of two magic tees T, T'each having four branches 1, 2, 3, 4 (first ring-shaped conduit), 1', 2 ', 3', 4 '. (Second ring-shaped conduit). The two rings terminate on both sides of the cylindrical oven 5 '.

Alternatively, although not shown, it is possible to add a third ring-shaped conduit supplied by two other magnetrons and orthogonal to the other two magnetrons. That is, it is on a horizontal plane in FIG.

FIG. 9 schematically shows a further device. Here microwave energy is radiated in the slots 18 in the open applicator structure 5, which allows the product to be treated to move past the slots.

This slot guide, which emits to a substance or object placed in an enclosed space, is the basis of many high performance applicators, although it is difficult to obtain a uniform distribution of the electromagnetic field in the vicinity of the slot. (Especially Sebastien Keller, These de D
(See octorat, Universite de Henri Poincare (Nancy 1), 6 November 1997)
. The problem is simplified by feeding the slot guide from two magnetrons.

In such a device as shown in FIG. 9, an electromagnetic field radiator is illustrated which gives a distribution that is uniform in the length direction and uniform in the direction perpendicular to the slots. In contrast to the device of the above figures, which is rather concerned with batchwise processing, it allows continuous processing. It should be noted that the slot 18 is not located in the middle of the height, but rather between 2/3 and 3/4 of the height. The radiating slot guide preferably comprises slanted flaps 19,20.

Returning to the details of the dual balanced mixer, its role is to continuously observe and process the changes in the parameters measured by the sensors 13, 14 according to the principle shown in FIG.

A reference microwave signal R is supplied to their inputs to these dual balanced mixers. They then vectorically detect only all waves that are in phase with the reference signal and only those waves that are in phase with the reference. Next signal
Pi11, Pr11, Pi12 and Pr12 are either images of the waves reflected on each branch 3 and 4 or an unbalanced image of the waves reflected on each face of the object, or transmitted from each magnetron Can be combined to obtain an unbalanced image of the waves.

Pi 11 indicates the incident power emitted from the magnetron 11, and Pi 12 indicates the incident power emitted from the magnetron 12. Pr11 indicates the reflection power toward the magnetron 11, and Pr12 indicates the reflection power toward the magnetron 12.

This information, which characterizes the amplitude and phase of the relevant waves, makes it possible to act on the coordination of the four adapters as a function of the desired treatment on a fixed schedule. Since it is known how the fundamental wave circulates in the circuit and how it wants to circulate the fundamental wave, certain schedules can obviously be applied.

Conveniently, the adapters emit their output signals to the processor. This may be turned into a simple handheld computer. If necessary, change their absolute or relative position so that they always remain at the optimal schedule,
The processor sends control commands to the adapters 6, 7, 8, 9.

Direct measurement of the electromagnetic field distribution in a product by using one (see above) or two or more antennas and by using a dual balanced mixer whose reference signal is the incident wave emitted from each magnetron However, this allows the procedure to be performed again. It is possible to isolate the value of the electric field created by each magnetron.

It is possible to feed the signal emitted by a single magnetron 11 to the reference path of a dual balanced mixer without using a directional measuring coupler. The magnetron is typically installed in a rectangular conduit in front of the short circuit. The position is chosen taking into account that the magnetron 11 operates according to its output and emits its total power into the conduit in the opposite direction. Magnetron 1
A ring circuit can be mounted at the bottom of the short circuit so that a wave of amplitude proportional to the transmission of 1 is sensed under the influence of magnetism. This loop circuit can feed a dual balanced mixer.

Since the oven comprises at least four impedance adapters, in other words the four adapters are different because each adapter has two degrees of freedom in the lateral position and the amount pushed in and has a total of eight adjustments. The automatic control of oven conditioning as described above in form is complicated. It should be noted that the oven is supplied by at least two magnetrons, i.e. the electromagnetic field spreading in the oven or in every branch of the ring is a variable first-order combination of the electromagnetic fields emanating from each magnetron. Therefore, it is necessary for the sensor to select a share of the electromagnetic field emanating from each magnetron, and for the sensor to provide two types of information regarding amplitude and phase.

These conditions cannot be guaranteed in a conventional detector with a diode, which measures only the amplitude of the total electromagnetic field. On the other hand, the intended purpose can be achieved by using a simple mixer. A mixer is a detector supplied with two electrical signals. One is called the signal S and the other is called the reference R. This input is often referred to in the technical literature by the expression "local oscillator". A simple mixer provides a non-zero voltage only when the two signals R and S are at the same frequency and in phase. This voltage has an amplitude S
And is proportional to the cosine of the phase S with respect to R. That is, V = S · cos ψ.

It is known how to make a dual balanced mixer with two simple mixers arranged in parallel and a suitable phase shifter. When the signal S having the same phase and the reference R are supplied to the dual balanced mixer, the dual balanced mixer gives two output voltages proportional to S · cosφ and S · sinφ.

For example, if the signal R is a wave from the magnetron 11, then the composite signal coming from both magnetrons can be used for the input S of the dual balanced mixer. As a result, the output of the dual balanced mixer detects only the signal R, ie the share of the electromagnetic field in phase with the wave emitted by the magnetron 11. In addition, the dual balanced mixer provides the amplitude and phase of the detected shares. These two outputs allow the desired impedance adapter to be adjusted.

Returning to FIG. 10 which shows a flow chart for the adjustment of the four impedance adapters 6-7-8-9, two directional measuring couplers 13,14 are used to couple the tees between the magnetron and the impedance adapters 8,9. It can be provided in branches 3 and 4.

Each measurement coupler provides two signals, Pi11, Pr12, Pi11, Pr12, circulating in the relevant branches, respectively, for the incident and reflected waves respectively.

If the dual balanced mixer uses the incident wave Pi11 as the reference signal R,
If the signal S has a reflected wave Pr12, its output will show the amplitude and phase of the wave in phase with the outgoing wave of the magnetron 11. As will be apparent from the above, these outputs will cancel the waves emitted from the magnetron 11 and reflected by the surface 13 of the object or substance 10 if the adapters 6 and 7 are symmetrically positioned. It is possible to adjust to.

Adjusting the symmetry of the adapter is another dual, where its reference R is provided by the signal Pi12 and its signal path is supplied with the signal Pr11 by devising things such that these outputs are also cancelled. It can also be controlled by the output S of the balanced mixer.

If the reference R of the third dual balanced mixer is supplied with the signal Pi11 and its signal path is supplied with the signal Pr11, the reflected wave received by and emitted from the magnetron 11 is measured, And the information about the phase is available directly at its output. Therefore, the reflected wave can be canceled by adjusting the impedance adapter 8 so that the voltage becomes zero.

According to the same procedure and in the same spirit, if the signal Pi12 is supplied to the reference path R of the fourth balanced mixer and the signal Pr12 is supplied to the signal path S, the magnetron 12 does not receive any reflected wave. Thus, information is output enabling adjustment of the impedance adapter located in front of the magnetron 12.

In the flow chart of coordination of the four impedance adapters shown above, four dual balanced mixers are used, whose reference path R contains the signals collected by the two directional couplers in front of the magnetron. Supplied. Adjusting the impedance adapter is equivalent to trying to zero the output from these dual balanced mixers.

In other words, the adjustment is a) by crossing the reflected signal Pr from the magnetron 12, ie Pr12, with the incident signal Pi of the magnetron 11, ie Pi11, b) the reflection from the magnetron 11. By crossing the signal Pr, Pr11, with the incident signal Pi, i.e. Pi12, of the magnetron 12, c) by combining the signal Pr11 with the signal Pi11, and d) by combining the signal Pr12 with the signal Pi12, This is done by canceling the resulting output signal from the dual balanced mixer.

FIGS. 10 a to 10 d correspond to each of the above combinations of symbols a) to d). Figure 10a
And in FIG. 10b, the symmetry adjustment involves branch 1 and 2 forming a ring upstream of the oven 5.
By adjusting each of the adapters 6 and 7 located at 1. In FIG. 10c the adapter 8 located at branch 3 is adjusted and in FIG. 10b the adapter 9 located at branch 4 is adjusted.

This flowchart may be modified without departing from the scope of the invention. First, as already mentioned above, the antenna located at the bottom of the short circuit piston allows the reference path R of the dual balanced mixer to be fed with the extracted signal as close as possible to the magnetrons 11 and 12.

For best results, the distribution of the total electromagnetic field acting on the product can also be evaluated and act on the adjustment of the four impedance adapters. Indeed, considering the antenna 15 acting as a sensor located in the center of the product shown in FIG. 6, it shows the whole field. Electromagnetic field, ie the component 1 of the share emitted from the magnetron 11.
To evaluate 1, it is sufficient to connect this antenna to the signal path S of the fifth dual balanced mixer in which Pi11 is supplied to the reference path R.
Obviously then, the four impedance adapters will be adjusted together so that the amplitude of the component 11 of the electromagnetic field distribution is maximized.

Similarly, the sixth dual balanced mixer in which the reference path R is Pi12 and the signal path S is wired to the antenna 15 is the electromagnetic field spreading in the center of the product (
It supplies information about amplitude and phase for component 12 (which originates from magnetron 12). If the four impedance adapters are properly adjusted, it should be minimal.

As detailed above and as shown in FIG. 4, this adjustment is intended to emit a maximum uniform distribution of the substance or object placed on the applicator 5. By accomplishing this adjustment in different ways, it is also possible to create special spatially non-uniform distributions, as described above.

As mentioned above, the present invention thus continuously adjusts their output frequencies as a function of the signals emitted by the dual balanced adapter and ensures an optimum distribution to the substance or object. , A heating system including the adjusting means and the control means of the adapters (6,7,8,9) described above.

The dual balanced mixer is a commercially available device. These are manufactured, for example, by ANAREN and MINI-CIRCUITS in the United States.

The present invention can be implemented in any type of microwave system for the defrosting or cooking of food or the heating of drinks, and also for industry in the food industry or more generally in the material processing industry.

A particularly beneficial application is always an extremely expensive operation, especially for infectious wastes, such as W, so that the waste can be dumped or reused rather than incinerated.
For the treatment of waste as described in the example of O 97/44069. Such a system could lay the foundation.

[Brief description of drawings]

FIG. 1 is a basic schematic diagram of an exemplary applicator having a Magic Tee (T) and its associated ring of a microwave heating or treatment system of the present invention.

FIG. 2 is a schematic perspective view of the magic tee of the applicator shown in FIG. 1 (eg, as seen by an observer along the axis delineated by arrow P).

FIG. 3 is a detailed view of an impedance adapter with a plunger rod for the applicator as in FIG.

FIG. 4 shows the steady-state distribution of the electromagnetic field produced by each of the magnetrons and its coupling in the ring.

5 is an external perspective view of the first embodiment of the system of the present invention according to the basic diagram of FIG. 1. FIG.

FIG. 6 is a view corresponding to FIG. 5 in which a sensor is shown which allows adjustment of the operation of the magnetron.

FIG. 7 shows another spatial arrangement of the inventive system with two additional waveguides located at the input of the applicator between the branch and the applicator.

FIG. 8 shows yet another spatial arrangement of the inventive system with four magnetrons (twice the two magnetrons).

FIG. 9 shows yet another layout with a microwave slot applicator that is advantageous for continuous processing of material past slots that emit microwave energy.

FIG. 10 (FIGS. 10a-10d) together show in schematic form the principle of measurement and the principle of calculation used in a dual balanced mixer to regulate the action of the ring.

─────────────────────────────────────────────────── ─── Continued front page    (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE), OA (BF, BJ , CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K E, LS, MW, SD, SL, SZ, TZ, UG, ZW ), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, C R, CU, CZ, DE, DK, DM, EE, ES, FI , GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, K Z, LC, LK, LR, LS, LT, LU, LV, MA , MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, S K, SL, TJ, TM, TR, TT, TZ, UA, UG , US, UZ, VN, YU, ZA, ZW

Claims (11)

[Claims] 1. A microwave system for heating or treating an object or substance, comprising an applicator or an oven (5) supplied by two separate magnetrons (11, 12), said magnetron comprising a magic tee or Mounted on the coupling branch (3, 4) of the directional coupler forming a ring, the other coupling branch (1, 2) irradiates the substance (10), and the impedance adapter (8, 9), To the branch (3, 4) and / or before the magnetron (11, 12) to decouple the action of the magnetron and transfer the total power emitted from the magnetron to the substance or object. , A microwave system for heating or treating an object or substance, characterized in that it is provided. 2. An impedance adapter (6, 7) is capable of canceling the waves received by each of the magnetrons reflected by the applicator (5), and yet receiving the share of the waves emitted from said magnetron. Characterized in that it has one or more dual balanced mixers, the reference being supplied by one magnetron, to detect in all the waves and adjust the impedance adapters (6, 7) The heating system according to claim 1. 3. A dual, having several adjusting circuits, which make it possible to modify the distribution of the waves emitted from each of the magnetrons, transmitted to the applicator (5) and reflected by said applicator, Adjust the above circuit that detects the distribution of the waves emitted by each of the other magnetrons in the balanced mixer reference path from all the received waves and modifies the distribution of the electromagnetic field acting on the object or substance. A heating system according to claim 2, characterized in that it is supplied by a magnetron. 4. A dual mixer reference path is provided by an auxiliary generator which stabilizes its frequency to one frequency of a magnetron, the frequency of which is provided by an auxiliary generator whose frequency is shifted from the frequency of the magnetron by a fixed value. 4. A heating system according to claim 2 or 3, characterized in that it is supplied from the magnetron to the reference path of the dual mixer after level equalization. 5. A method for controlling a system with two separate magnetrons, characterized in that the distribution coming from each of the two magnetrons is separated from the electromagnetic field generated by them with the aid of a dual balanced mixer. 6. A method as claimed in claim 5, characterized in that, with the aid of a balanced mixer, the adjustment of the adapter is continuously tuned so as to optimize the aperture parameters of the magnetron. 7. A method according to claim 6, characterized in that adjustments are made to obtain a constant and uniform maximum distribution over the substance or object. 8. The adjustment comprises: a) crossing the reflected signal Pr, ie, (Pr12), from the magnetron (12) with the incident signal Pi, ie (Pi11), of the magnetron (11); and b) the magnetron ( By crossing the reflected signal Pr from (11), i.e. (Pr11), with the incident signal Pi of the magnetron (12), i.e. (Pi12), c) by combining the signal (Pr11) with the signal (Pi11) 8. The method of claim 7, further comprising: d) canceling the resulting output signal from the dual balanced mixer by combining the signal (Pr12) with the signal (Pi12). 9. The method of claim 6, wherein adjustments are made to obtain a modulated distribution for the substance or object. 10. Means in the method according to any one of claims 5 to 9,
A control means for the adapters (6,7,8,9), which continuously tunes said adapters as a function of the signals carried by the dual balanced adapters and ensures an optimal distribution for substances and objects. The automated heating system according to any one of claims 1 to 4, wherein. 11. Claim 1 in the treatment of infectious waste, especially hospital waste.
Use of the system according to any one of 5 to 11 above.